1. Field of the Invention
The present invention relates to human powered ground transportation vehicles having two or more wheels, such as bicycles and the like. More particularly, the present invention relates to a bicycle, or similar vehicle, constructed for convenient manual transformation between an erected operating configuration, for transporting one or more passengers, and a compactly folded position, for facilitating toting the vehicle about as well as stowing it away.
2. Description of the Related Art
Today, bicycles enjoy wide recognition and favorable acceptance as a means of transportation. Bicycle design and construction has evolved tremendously over the years, and further evolution will likely continue long into the future.
In the early days of development, both steering and powering functions for the typical bicycle were carried out via the front wheel. A typical steering arrangement included a handlebar, attached atop a steering column, as a means for operator controlled steering of the vehicle. In this regard, the handlebar/steering column arrangement was designed to rotate in concert with the front wheel. Any manual rotation of the handlebar effected an identical angular rotation of the front wheel. For motion, early systems typically supplied driving power, derived from a rider's leg work, directly to the front wheel. In this regard, the drive systems generally included a pair of rider engagable foot pedals. One pedal was positioned laterally outward of, and alongside, each outer face of the wheel. Connection means were provided to rigidly attach the pedals at opposing ends of the front wheel axle.
Although effective for certain limited purposes, the early direct drive systems were characterized by various disadvantages. For example, the typical human operator was physically incapable of rotating the front wheel assembly, via the foot pedals, at such a rate (revolutions per minute) as required in order to achieve high vehicle speeds (i.e., more than 15 mph). Further, high speed travel could not be achieved even when such a direct drive system was used in combination with a large-diameter front wheel (e.g., five feet). Another disadvantage, which was characteristic of the early direct drive systems, was incurred due to the rigid attachment of the foot pedals at the front wheel axle. Such attachment required that the pedals rotate about the vehicle's steering axis upon rotation of the front wheel. This characteristic made vehicle steering maneuvers highly cumbersome for the operator.
Subsequent design efforts, aimed at permitting an increase in top vehicle speed without requiring the use of a large-diameter front wheel, eventually lead to the introduction of gears into the vehicle drive system arrangement. Achievable bicycle top speeds increased tremendously as a result. The developed gears and the various systems of gears, additionally, permitted the foot pedals to be fixed with respect to the vehicle frame instead of at the front wheel axle. Accordingly, the problems due to pedal rotation during steering could be avoided. The great successes enjoyed through the use of gears in the various bicycle operational systems prompted still further development efforts. Today, developers continue such efforts to create new and/or improved gears and gear arrangements capable of satisfying a variety of targeted needs and goals.
Numerous and varied additional changes and improvements in bicycle design have been observed over the past century. The typical bicycle of today generally includes a metal frame mounted on two wire-spoked wheels with one behind the other, a seat, handlebars for steering, and a pair of pedals by which it is driven. The majority of present day bicycles are constructed so that steering is accomplished via the forwardly positioned wheel and drive (power) for the vehicle is provided via the rearwardly positioned wheel. The overall length of such arrangements tend to exceed five feet. The vehicle weight is sometimes minimized by utilizing light weight materials, such as aluminum or fiber reinforced resins. Bicycle constructions which employ such materials can achieve vehicle weights as low as 10 pounds.
In spite of the widespread acceptance of bicycles as a means of transportation highly useful for many purposes, riders nevertheless often encounter problems upon reaching a destination point. For example, adequate facilities may not exist at a particular destination for storing the bicycle. Unfortunately, when a bicycle is temporarily parked and left unattended, it often becomes a target for theft and/or vandalism. Another problem can be encountered if the bicycle is used during, or in making, only a limited portion of a trip. In such a situation, the use and/or presence of the bicycle, especially a large and/or heavy one, will not always be desirable. For example, it may become necessary for a rider to carry the bicycle onto a different transportation vehicle for a time (e.g., a bus, van, train, plane, etc.). Such a situation could arise when the only reasonable means available to get to a particular desired location is by way of a common public transportation vehicle, but the rider contemplates a future need to use the bicycle after arriving at the location. It is not only inconvenient to hand carry presently known ordinary bicycles, but also those constructed of very light weight materials. This is due to the fact that many problems arise primarily as a result of vehicle length. Typical vehicle lengths are often equal to, or greater than, average human height. Thus, problems caused merely by the spatial outlay of a vehicle can deter or prohibit a rider from carrying it about and/or stowing it safely away during periods of non-use (e.g., while at the workplace).
Development efforts, focused at reducing the vehicle carrying configuration length and width, have given rise to bicycle designs incorporating various folding schemes. Although the known folding bicycle designs exhibit a number of differences from the typical features of ordinary bicycles, they have all continued to utilize the typical basic steering and power drive arrangement employed with ordinary bicycles. So far, the reductions in carrying configuration size (volume) achieved by the known folding bicycles have not proven sufficient to promote their general recognition and acceptance.
In order to operate a typical bicycle, a force (power) must be imparted by the rider's legs towards the vehicle pedals. Generally, this operating force extends in a substantially vertical direction. Accordingly, the rider usually assumes a riding position which facilitates the application of such force. The usual position assumed by the rider tends to make the overall vehicle/rider height greater than four feet. As a consequence, a large frontal view cross sectional area of the rider's body is exposed which acts as a source of drag.
There is a known bicycle design-type which reduces the frontal cross sectional area exposed by a rider, as compared to that encountered with the more typical bicycle constructions. Such vehicles are known as recumbent bicycles. Recumbent bicycles are designed so that the rider assumes a lay-back position during vehicle operation. Recumbent bicycles have been the predominant design-type used by riders in setting the currently held short distance speed records. Despite their successes, recumbent bicycles are recognized to present certain problems of their own. Recumbent bicycles equipped with typical front wheel steering and back wheel drive require the use of long drive chains which are positioned under the rider. Unfortunately, such drive chains are a potential source of drag since they tend to add to the vehicle height and, thus, to the frontal view cross sectional area.
As can be readily ascertained from the foregoing, various improvements in bicycle design and construction are desirable.
It is a general object of the present invention to provide a human powered ground transportation vehicle having two or more wheels.
It is a particular object of the present invention to provide a bicycle, or similar vehicle, constructed for convenient manual transformation between an erected operating configuration and a compactly folded position.
It is a further object of the present invention to provide a compactly folded bicycle, or similar vehicle, which can be readily carried by hand and/or stowed away, as desired.
It is a related object of the present invention to provide a compactly folded bicycle, or similar vehicle, which occupies a reduced hand-carrying configuration volume compared to that occupied by the known constructions in the art.
It is also a related object of the present invention to provide a compactly folded bicycle, or similar vehicle, which demands less space for storage than that required for storing any of the known constructions in the art.
An additional object of the present invention is to provide a human powered ground transportation vehicle which has a relatively low frontal view cross sectional area in order to minimize drag.
It is a related object of the present invention to provide a low drag, human powered ground transportation vehicle, having one forwardly positioned wheel and at least one rearwardly position wheel, wherein the construction is uniquely adapted to utilize the forwardly positioned wheel both for effecting vehicle steering maneuvers as well as for powering the vehicle.
It is also a related object of the present invention to provide a front wheel steering, front wheel drive, low-drag, human powered ground transportation vehicle equipped with a uniquely designed gear arrangement for the vehicle drive system; wherein the gear system design permits both highly effective vehicle drive system performance and, at the same time, good overall vehicle performance substantially unaffected by the structural presence and/or the physical operations of the gear system.
It is yet a further object of the present invention to provide a foldable bicycle, or similar vehicle, which is relatively simple and low in cost, yet is reliable and efficient as a means for transportation.